Refining steel.



UNITED STATES PATENT ornicn.

OTTO THALLNER, OF BrsinrneKni'irrn, GERMANY, iissicnoa TO 'rnn FIRM or BISMARGk- HUTTE, OF BISVARCKHUTTE. GERMANY. I

REFINING STEEL.

1 0 all whom it may concern:

Be it known that I, OTTO TIIALLNER, metfollowing is. an exact specification.

This invention relates to a process for the production of high quality steel, in which the refining is cffectedin electric furnaces.

In the refining; of -steel in Bessemer, Martin or Thomas furnaces it'has alreadybeen proposedto pass the steel after treatment in these furnaces into a crucible, which is lined with an acid lining for instance a fire proof lining; in which silieic arid forms the principal According to the present iiinace having a basic lining. for example one in which lime forins the principal component, is passed into a crucible having an acid fire proof lining. The steel previously refined in the electric furnace is allowed to stand in the crucible for a few hours so that the remainder of the slag which has not'been sepa rated by the reaction in the furnace settles on tlie'top of the material in the crucible. l

have found that such a separation cannot be produced by prolonged treatment in'tlie electric furnace for the reason that the disturbance of the iiiate'rialbetween the electrodes is too violent to {)(J'ii'iifl of the settling oftlie finely mixed particles of the slag which have not been removed by the reaction and which "are distributed through. the molten mass like the constituents in an emulsion. \iliill alfowed to remain in the crucible however the influence of the basic lin'ed electric furnace is coiinter-balanceil as in the crucible silicon is taken up and thereby the steel receives the ment of the'sfeel has been carried out as far. as possible in such a furnace. the steel is treated in an electric furnace and then al lowed to settle in a crucible as described above. In this way, thecxtraetion of the phosphorus, sulfur and oxygen. can be ef.

feete'd to a much greater extent than is possible maNfaflnri-and like furnaces. Further by treating the steel first in ai Martin or like Specification of Letters Patent.

Application filed'lune 17, 1908.

-ohi ained.

Patented April 27, 1909.

Serial Nu. 439,043.

furnace and then .earrying out the refining, to a greater extent'in an electric furnace and thereafter allowing the fine slag to separate in a crucible with an acid lining a much more economical treatment is obtained.

tion of alloys of iron in a very controllable manner or tliQfLdditiOll of modifying agents as is usual in the crucible process. 'lhese additions can only be added with great difficulty in an electric furnace as the temperature conditions in the electric furnace are so variable that when the additions "usual inthe crucible process are made, totally differ ent results as regards grain and structure of the metal and other physical qualities are These difficulties can be avoided accordinglo the present )rocess by passing the steel into the crucible ;efore the addition of the iiio(-lif' 'vingconstituents. Likewise the carboi-iizing of the steel can take place in the crucible by means of suitable known carbonizing agents.

1 laim:

1. The process for refining steel consisting in previously refining the steel in a basic electric furnace and afterward leading said iiefined steel int a crucible for thepurposeof settling and further treatment.

2. Tire process for, refining steel consisting in previously refining the steel in a basic lined electric furnace and then treating said partially refined steel ina crucible for the purpose of settling and adding modifying additions to the metal in said crucible.

3. The process for refining steel consisting in previously refining the steel in a basic lined electric furnace and afterward leading .said partially refined steel into a crucible for. the purpose of settling and addingcarbonizing agents to said metal in the crucible.

4. The process for the production of highly G0 The process also permits of the produe-- refined steel comprising treating: the steel in a fuel heated furnace, then carrying the refining to a higher degree in a basic liii'ed elec- 10o tric fur nace,'after which the steel so refinedis allowed 'to settle and take up acidpro[perties in a crucible;sul istantially as descri aid. in witness whereof I have hereuntoset my hand in the presence of two witnesses.

()T'fO 'fllA liliN 16ft. fViti-iessesf I f lnns'r Kii'iiL, EaNsr Kiirz. 

